This invention relates to the growth of GaAs films and more particularly to a method for epitaxial growth of GaAs films and device configurations independent of GaAs substrates.
Heretofore, active epitaxial layers and/or buffer layers of GaAs have been grown using bulk GaAs substrate material as the host material on which the epitaxial growth is initiated. In the prior art growth process, non-stoichiometric interface problems arise at the "growing surface". A prior-art method of forming and removing an electrical element from a deposited substrate is taught by U.S. Pat. No. 4,021,767. This patent does not concern itself with critical lattice matching and thermal matching to obtain high crystalline perfection. It is involved in obtaining thin electrical detectors of a specific thickness in order to make Hall measurements more accurately.
U.S. Pat. No. 4,118,857 is directed to the growth of epitaxial layers which are single crystal, with uniform thickness and electrical properties. The substrate has a different composition or electrical properties from that of the epitaxial layer. Hall measuring devices are made by this process.